<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8">
    <title>样式示例</title>
    <style type="text/css">
        h3 {
            color: red;
        }

        div {
            color: red;
        }

        p {
            color: red;
        }

        span {
            color: red;
        }
    </style>
</head>

<body>
    <h3>这是 h3 元素的内容</h3>
    <div>这是 div 元素的内容</div>
    <p>这是 p 元素的内容</p >
    <span>这是 span 元素的内容</span>
</body>

</html>